Alcator C-Mod Run 950504 Information

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Miniproposals
Miniproposal:078
Date Filed: 2/8/1995
Title:ICRF Heating in H-mode Plasmas
First Author:Yuichi Takase
Session Leader:Yuichi Takase (shots 1-28)

Operators
Session leader(s):Yuichi Takase
Physics operator(s): Unknown
Engineering operator(s): Unknown

Engineering Operator Run Comment
Rf

Session Leader Plans

Physics Operators Plans

Session Leader Summaries
Entered: Jul 7 2004 03:49:13:663PM
Author: To Be Determined
Day 1 of H-mode run
Starting from 950331038
Scan density and plasma equilibrium (outer gap, X-point, etc.)

After a slow start because of problems with RF fault detection circuits
and plasma control, we had a productive run (shots 013 - 025) and were
able to explore effects of plasma equilibrium (outer gap, X-point position)
and target density. The outer gap was varied from 1.2cm to 2.2cm, and
some variation of the X-point location was attempted. The target density
was varied over a limited range, nel_04=1.0e20 to 1.3e20. Contrary to
expectations, higher H-factors were obtained with more gas puffing (higher
density). Over the limited range of X-point locations investigated, there
were no great changes in the H-factor. Even with a relatively small gap
of 1.2cm we were able to obtain a reasonable H-mode (shot 013). The
highest H-factor obtained today was about 1.35, comparable to the best
achieved so far (up to about 1.4).

We will continue H-mode studies tomorrow, starting with a current scan.

Shot
001 pl disrupted early
002 pl lowered Ip, disrupted early
003 fiz loaded 950502031
004 pl early disruption
--- cell access to fix antenna diagnostics
005 fiz
006 pl disrupt @ 0.7sec
007 pl lasted till 1.0sec, D:0.85MW, E:0.7MW, ramping density
008 fiz
009 fiz
010 pl disrupt @ 0.75sec
011 pl disrupt @ 0.67sec
012 fiz
013 pla H-mode, first full shot, D:1.3MW, E:0.95MW
nel_04(pre-RF)=1.15e20, Rgap=1.2cm, zmagx=-0.5cm, W_EFIT=91kJ
--- delay, computer problem
014 pla no H-mode, D:0.85MW, E:0.5MW
nel_04(pre-RF)=1.15e20, Rgap=1.5cm, zmagx=-0.7cm, W_EFIT=65kJ
015 pla weak H-mode, D:0.8MW, E:0.5MW
nel_04(pre-RF)=1.12e20, Rgap=1.7cm, zmagx=-0.5cm, W_EFIT=82kJ
016 pla weak H-mode, D:1.0MW, E:0.6MW
nel_04(pre-RF)=1.13e20, Rgap=1.7cm, zmagx=-0.4cm, W_EFIT=82kJ
017 pla programmed Xpt down by 0.5cm
H-mode, D:1.4MW, E:0.65MW
nel_04(pre-RF)=1.10e20, Rgap=1.7cm, zmagx=-0.5cm, W_EFIT=91kJ
018 pla larger outer gap
H-mode, D:1.4MW, E:0.65MW
nel_04(pre-RF)=1.0e20, Rgap=1.9cm, zmagx=-0.6cm, W_EFIT=89kJ
019 pla moved X-pt in and down, less density programming during RF
H-mode, D:1.45MW, E:0.7MW
nel_04(pre-RF)=1.0e20, Rgap=2.0cm, zmagx=-0.6cm, W_EFIT=87kJ
020 pla lower density
H-mode, D:1.3MW, E:0.6MW
nel_04(pre-RF)=1.0e20, Rgap=2.1cm, zmagx=-0.4cm, W_EFIT=80kJ
021 pla cut gas puffing down (prior to rf)
weak H-mode, D:1.3MW, E:0.6MW
nel_04(pre-RF)=0.84e20, Rgap=2.2cm, zmagx=-0.7cm, W_EFIT=74kJ
022 pla higher density (programmed to 1.4e20), disrupt @ 0.49sec
023 pla H-mode, D:1.3MW, E:0.6MW, disrupted @ 0.82sec
nel_04(pre-RF)=1.3e20, Rgap=2.0cm, zmagx=-0.6cm, W_EFIT=91kJ
024 pla RCUR ramp 2.5mm outward over 0.72 to 0.8sec
no H-mode, D:1.3MW, E:0.55MW, disrupted @ 0.78sec
nel_04(pre-RF)=1.3e20, Rgap=2.2cm, zmagx=-0.6cm, W_EFIT=65kJ
025 pla load density programming from shot 018
H-mode, D:1.3MW, E:0.6MW, disrupted @ 0.87sec
nel_04(pre-RF)=1.0e20, Rgap=2.0->1.2cm, zmagx=-0.5cm, W_EFIT=85kJ


Physics Operator Summaries

Session Leader Comments
May 4 1995 01:42:52:120PM950504001Yuichi TakaseDay 1 of H-mode run
Starting from 950331038
Scan density and plasma equilibrium (outer gap, X-point, etc.)

shot 001 disrupted early

May 4 1995 01:43:54:970PM950504002Yuichi Takaseshot 002 lowered Ip, disrupted early

May 4 1995 01:44:13:370PM950504003Yuichi Takaseshot 003 loaded 950502031

May 4 1995 01:44:34:660PM950504004Yuichi Takaseshot 004 early disruption

May 4 1995 01:45:09:760PM950504005Yuichi Takaseshot 005 shot delayed (cell access to fix antenna diagnostics)
fizzle

May 4 1995 01:45:35:440PM950504006Yuichi Takaseshot 006 disrupt @ 0.7sec

May 4 1995 01:45:52:630PM950504007Yuichi Takaseshot 007 lasted till 1.0sec, D:0.85MW, E:0.7MW, ramping density

May 4 1995 01:46:16:070PM950504008Yuichi Takaseshot 008 fizzle

May 4 1995 01:46:25:720PM950504009Yuichi Takaseshot 009 fizzle

May 4 1995 01:46:49:660PM950504010Yuichi Takaseshot 010 disrupt @ 0.75sec

May 4 1995 01:47:01:470PM950504011Yuichi Takaseshot 011 disrupt @ 0.67sec

May 4 1995 01:47:12:410PM950504012Yuichi Takaseshot 012 fizzle

May 4 1995 01:47:44:900PM950504013Yuichi Takaseshot 013 first full shot, D:1.3MW, E:0.95MW
H-mode

May 4 1995 01:59:02:200PM950504013Yuichi Takaseshot 013 first full shot, D:1.3MW, E:0.95MW
H-mode, nel_04(pre-RF)=1.15e20, Rgap=1.2cm, zmagx=-0.5cm, W_EFIT=91kJ

May 4 1995 02:17:34:130PM950504014Yuichi Takaseshot 014 no H-mode, D:0.85MW, E:0.5MW
nel_04(pre-RF)=1.15e20, Rgap=1.5cm, zmagx=-0.7cm, W_EFIT=65kJ

May 4 1995 02:28:11:160PM950504015Yuichi Takaseshot 015 weak H-mode, D:0.8MW, E:0.5MW
nel_04(pre-RF)=1.12e20, Rgap=1.7cm, zmagx=-0.5cm, W_EFIT=82kJ

May 4 1995 02:55:31:800PM950504016Yuichi Takaseshot 016 weak H-mode, D:1.0MW, E:0.6MW
nel_04(pre-RF)=1.13e20, Rgap=1.7cm, zmagx=-0.4cm, W_EFIT=82kJ

May 4 1995 02:56:44:390PM950504017Yuichi Takaseshot 017 programmed Xpt down by 0.5cm
H-mode, D:1.4MW, E:0.65MW
nel_04(pre-RF)=1.10e20, Rgap=1.7cm, zmagx=-0.5cm, W_EFIT=91kJ

May 4 1995 04:17:30:000PM950504018Yuichi Takaseshot 018 larger outer gap
H-mode, D:1.4MW, E:0.65MW
nel_04(pre-RF)=1.0e20, Rgap=1.9cm, zmagx=-0.6cm, W_EFIT=89kJ

May 4 1995 04:17:51:930PM950504019Yuichi Takaseshot 019 moved X-pt in and down, less density programming during RF
H-mode, D:1.45MW, E:0.7MW
nel_04(pre-RF)=1.0e20, Rgap=2.0cm, zmagx=-0.6cm, W_EFIT=87kJ

May 4 1995 04:18:16:510PM950504020Yuichi Takaseshot 020 lower density
H-mode, D:1.3MW, E:0.6MW
nel_04(pre-RF)=1.0e20, Rgap=2.1cm, zmagx=-0.4cm, W_EFIT=80kJ

May 4 1995 04:19:05:470PM950504021Yuichi Takaseshot 021 cut gas puffing down (prior to rf)
weak H-mode, D:1.3MW, E:0.6MW
nel_04(pre-RF)=0.84e20, Rgap=2.2cm, zmagx=-0.7cm, W_EFIT=74kJ

May 4 1995 04:19:23:700PM950504022Yuichi Takaseshot 022 higher density (programmed to 1.4e20), disrupt @ 0.49sec

May 4 1995 04:38:30:220PM950504023Yuichi Takaseshot 023 H-mode, D:1.3MW, E:0.6MW, disrupted @ 0.82sec
nel_04(pre-RF)=1.3e20, Rgap=2.0cm, zmagx=-0.6cm, W_EFIT=91kJ

May 4 1995 06:07:11:320PM950504024Yuichi Takaseshot 024 RCUR ramp 2.5mm outward over 0.72 to 0.8sec
no H-mode, D:1.3MW, E:0.55MW, disrupted @ 0.78sec
nel_04(pre-RF)=1.3e20, Rgap=2.2cm, zmagx=-0.6cm, W_EFIT=65kJ

May 4 1995 06:07:44:100PM950504025Yuichi Takaseshot 025 load density programming from shot 018
H-mode, D:1.3MW, E:0.6MW, disrupted @ 0.87sec
nel_04(pre-RF)=1.0e20, Rgap=2.0->1.2cm, zmagx=-0.5cm, W_EFIT=85kJ

Physics Operator Comments

Engineering Operator Comments
ShotTimeTypeStatusComment
108:32:31:410AMPlasmaOk
208:50:10:940AMPlasmaOk
309:09:31:080AMPlasmaOk
409:20:37:790AMPlasmaOk
511:07:31:080AMPlasmaOk
611:17:50:980AMPlasmaOk
711:34:55:530AMPlasmaOk
811:57:34:170AMPlasmaOk
912:14:39:740PMPlasmaOk
1012:30:11:840PMPlasmaOk
1112:46:26:280PMPlasmaOk
1201:05:53:900PMPlasmaOkNo Faults.
1301:19:43:080PMPlasmaOkNo Faults.
1401:57:12:480PMPlasmaOkNo Faults.
1502:11:42:490PMPlasmaOkNo Faults.
1602:27:32:100PMPlasmaOk
1702:43:52:170PMPlasmaOkNo Faults
1802:59:14:470PMPlasmaOkNo Faults.
1903:17:45:420PMPlasmaOkNo Faults
2003:32:26:100PMPlasmaOkNo Faults
2103:46:45:060PMPlasmaOkNo Faults.
2204:01:56:610PMPlasmaOkNo Faults.
2304:17:15:900PMPlasmaOkNo Faults.
2404:35:23:980PMPlasmaOkNo Faults
2504:51:11:710PMPlasmaOkNo Faults
2605:09:30:730PMTestOkScanner test
2705:28:23:760PMTestOkscanner test
2805:45:37:820PMTestOkScanner test